Incandescent lamp mount



Nov. 10, 1964 s. E. SWASEY ETAL 3,156,843

INCANDEISCENT LAMP MOUNT Filed Oct. 27, 1960 4 Sheets-Sheet 1 997 figsa-Q zb z i 22 |8 j l 2 SAMUEL E. SWASEY 2e KENTON R. BAGLEY INVENTORS 2(J IEb fi BY n ATTORNEY 1964 s. E. SWASEY ETAL 3,

INCANDESCENT LAMP MOUNT Filed 001;. 27, 1960 4 Sheets-Sheet 2 2 I 40$,40) 2 40) 2b 4b 4b I 22 g-12 P g-19 fia-M SAMUEL E. SWASEY KENTON R.BAGLEY IN V EN TORS ATTORNE Nov. 10, 1964 s. E. SWASEY ETAL 3,155,843

INCANDESCENT LAMP MOUNT Filed Oct. 27, 1960 4 Sheets-Sheet 3 SAMUEL E.SWASEY KENTON R. BAGLEY INVENTORS ATTORNE Nov. 10, 1964 s. E. SWASEYETAL 3,

INCANDESCENT LAMP MOUNT Filed Oct. 27, 1960 4 Sheets-Sheet 4 PRIOR ARTSAMUEL E. SWASEY KENTON R. BAGLEY INVENTORS BY M ATTORN Y United StatesPatent 0 3,156,3 5.? ENQANBESCENT LAMP MfFUNT Samuel E. Swasey,Edgemere, Marbleliead, and Kenton R. llagiey, Beverly, Mass, assignorsto taylvania Electrio Products inc, a corporation of Delaware Filed(lot. 27, 1959, her, No. 65,426 4 -Claiins, ll. 313-271) This inventionrelates to the manufacture of incandescent l-amps and more particularlyto the fabrication of a mount structure for so-called 3-lite lamps andthe like. Lamps of this type are provided with two filamentsmechanically and electrically connected in such a manner that, incombination with suitable switching means, light of differentintensities may be obtained. For example, a 30-70400 watt lamp of thistype is one which is pr vided with a 30 watt filament and a 70 wattfilament. The mechanical and electrical mount structure on the one handand the aforesaid switching means on the other hand cooperate, in onemodification, to permit one to use the 30 watt filament, the 70 wattfilament or both in combination to provide an effective 100 wattfilament.

Despite the many advances which have been made in recent years in thedevelopment of high-speed automatic lamp manufacturing equipment and thedesign of mount structures particularly suitable for fabrication by thisequipment, prior to our invention many of the operations involved in thefabrication of a mount structure for this type of lamp have beenperformed manually or semiautomatically. One of the major reasons forthis is the fact that great care must be exercised in the maintenance,within very close tolerances, of substantially uniform effectiveelectrical length and physical configuration of the lamp filaments fromlamp to lamp in order to obtain substantially uniform lampcharacteristics and a relatively high degree of luminous efficiency.This factor of effective electrical length of the filament is a functionof the overall length of the wire itself, the t.p.i. (turns per inch) ofthe primary coiling and, in the case of coiled coils, the t.p.i. of thesecondary coiling.

Heretofore, in order to insure the attainment of these uniform qualitycharacteristics, mounting of the 3-lite filaments has been a manualoperation in which an operator adjusts the lead tip spacing whenmounting each filament. In the mount structure of the prior art, whichwill be described in greater particularity below, a pair of filamentsare attached at their ends to their respective lead-in wires and atleast two filament support wires are employed to support each of thefilaments in a crescent-shaped disposition. Each of these filamentsupport wires is embedded at one end in an arbor button and the otherend is looped around the filament intermediate its ends.

Many efforts have been exert d to effect modifications of this type ofmount structure in order to mike feasible the automatic fabrication ofthe mount structure for this type of lamp. For example, it has beensuggested that the two filaments with which lamps of this type areprovided be substantially linear, i.e., disposed substantially normal tothe longitudinal axis of the lamp and spaced from one another indifferent planes both horizontally and vertically. However, it has beenfound that a complex filament supporting arrangement must be providedand, despite this, attainment of a substantially uniform effectiveelectrical length of these filaments from lamp to lamp is exceedinglydifiicult to obtain. Although some success has been on joyed in the useof this type of mount structure when coiled filaments are used, it hasbeen quite unsatisfactory when one or both of the filaments are of themore efiicient coiled coil type because of the additional problems involved in the maintenance of substantially uniform effective electricallength of this type of coil.

In recent years certain improvements have been made in the design ofmount structures to provide for the automatic manufacture of singlefilament lamps in which the filament is disposed vertically, i.e.,substantially parallel to and in some cases substantially coincidentalwith the longitudinal axis of the lamp' Mount structures of this typeare disclosed for example in the co-pending applications of Swasey etal., Serial No. 839,796 filed September 14, 1959 now Patent #3,007,074and Serial No. 836,380 filed August 27, 1959 now Patent #1001073.

Since it is known that a coiled coil is more efiicient than a singlycoiled filament, it is particularly desirable that new mount structuresdesigned to permit fabrication thereof on high-speed automatic equipmentshould also be designed so that coiled coils may be used satisfactorily.

It is further desirable that a new mount structure be designed toprovide for the mounting of the two filaments in the 3-lite lampvertically.

in view of the foregoing, one of the principal objects of this inventionis to provide a 3-lite lamp in which both filaments are disposedvertically.

Another object of this invention is to provide a mount structure forthis type of lamp in which coiled coils may be used and their effectiveelectrical length maintained substantially uniform within very closetolerances.

A further object of this invention is to provide a new mount structurefor this type of lamp in which all of the mount fabricating operationsmay be performed on highspeed automatic lamp manufacturing equipment.

These and other objects, advantages and features are obtained, inaccordance with the principles of our invention, by a new and novelmount structure fabricated by new and novel mount manufacturingtechniques. In the fabrication of this mount structure only three.lead-in wires are fed to the head of the machine on which thefabricating operations are performed, despite the fact that four wiresare required, two for each of the two filaments. This is a significantimprovement over the art because it eliminates one article-feedingoperation. This is preferably accomplished by initially feeding a longlead-in wire and then in a series of fabricating steps forming andsevering from the free end thereof an extra short wire. Alternately, thelong lead-in wire may be provided with a hook portion intermediate itsends as well as a hook portion at the free end thereof, in which caseone end of each of the two filaments would be secured to one of thesetwo hook portions of the common lead-in wire. Another novel echniqueemployed in the fabrication of our new mount structure is the manner inwhich the assemblage of mount components is provided with a pair offilament support wires. In accordance with our invention a length offilament support wire, from which two filament support Wires are to beformed, is fed in substantially hairpin shape to the head of the machineat about the same time as h other mount components are fed, and insubsequent fabrication operations the adjacent free ends of this wireare sealed in spaced relationship in the stern press, the blght of thehairpin is severed and the free ends so defined are looped around theirrespective filaments and thereby provide two separate filament supportwires. This is also a significant contribution to the art since itrenders unnecessary the use of a filament support wire insertingapparatus widely used in the industry in the manufacture of this type oflamp.

Other structural features of the mount and novel techniques in thefabrication thereof will be apparent to those skilled in the art fromthe description below of a specific embodiment of our invention.

In the accompanying drawings, FIGURE 1 is an elevational View of themount components showing the relative position occupied by them afterthey have been fed to a head of the mount fabrication machine and beforeany operations have been performed thereon.

FIGURES 2 to 14 inclusive are fragmentary elevational views of theassemblage of mount components illustrating a preferred sequence offabricating steps employed to manufacture the mount.

FIGURE is an elevational view on an enlarged scale of the completemount.

FIGURE 16 is an elevational view of a finished lamp with the mount ofFIGURE 15 disposed thereon.

FIGURE 17 is an elevational view of a typical 3-lite lamp of the priorart.

In order to facilitate an understanding and appreciation of thesignificance of our invention over the prior art, the typical prior artmount structure illustrated in FIG- URE 17 will be described first. Thelamp of FIGURE 17 comprises an hermetically sealed lamp envelope 1 towhich a base 3 is secured. In the fabrication of the mount structureshown in FIGURE 17, three lead-in wires 5, 7 and 9, provided with hookson one end thereof, are fed manually to the head of a lamp stemfabricating machine because of the difficulties encountered inattempting to feed hooked lead-in wires automatically from a reservoirthereof. The head of the machine is provided with a stem 11 and an arbor13 automatically in a manner well known in the art. After the stem press15 has been formed and the lead-in wires 5, 7 and 9 sealed therein andthe arbor 13 sealed thereto, this unitary intermediate product structureis withdrawn from the stem-making machine and certain operations arethen performed thereon manually. An operator afiixes an extra short wire17 to the common lead-in wire 7 at a point somewhat below the hooked endthereof. The operator then manually feeds this intermediate productstructure into a filament support wire inserting apparatus. On thisapparatus, means are provided for forming an arbor button 23 on an endof the arbor l3, inserting thereinto one end of each of four filamentsupport wires and forming a pigtail on the free end of each of thesefour filament support wires 25. An operator then removes thisintermediate product structure from the filament support wire insertingapparatus and transfers it to a filament mounting operator who affixesfilaments 19 and 21 thereto. This operator secures one end of filament19 to the hooked end of lead-in wire 9, threads the filament through thepigtails formed on the free ends of one pair of filament support wires25 and then secures the other end of the filament 19 to the hooked endof the extra short wire 17. Similarly, the operator secures one end offilament 21 to the hooked end of lead-in 'wire 5, threads the filamentthrough the pigtails formed on the free ends of the other pair offilament support wires 25 and then secures the other end of filament 21to the hooked end of the common lead-in wire 7.

In view of the foregoing brief description of the typical mountstructure and method of fabrication thereof of a 3-lite lamp of theprior art, it will be readily appreciated that high-speed production ofthese articles is not possible. Some operations are performedautomatically, others are then performed manually and subsequentlyfurther automatic operations are performed, thus requiring severalarticle handling operations to be performed on the intermediate productstructures.

In the manufacture of the mount of this invention illustrated in FIGURE15, all of the article feeding operations and the article fabricatingoperations are performed automatically on an apparatus of the typedisclosed in US. Patent 2,637,144 issued to R. M. Gardner et al. on May5, 1953. The apparatus employed in the manufacture of the mountstructure of this invention is similar to that shown in the referencedpatent except that the apparaus is larger, provided with more heads, andprovided with a number of article working devices and tools to performthe various fabricating operations described below.

Suitable article feeding devices are employed to provide each head ofthe machine with the several mount components shown in FIGURE 1, namelya long lead-in wire 2, a length of filament support wire fed and shapedin substantially hairpin configuration and hereinafter referred to asthe hairpin a pair of short lead-in wires 6 and 8, a stem 10 and anexhaust tube 12. It will be noted that the stem 10 of FIGURE 1 andsucceeding figures is provided with a dot 14. The actual article is notnormally so provided but the illustrations thereof in the drawings havebeen provided with this dot in order to facilitate an understanding ofthe relative disposition of the articles of work during the fabricatingoperations.

With the articles of work disposed in the relative position as shown inFIGURE 1, conventional stem working operations are performed thereon,namely heating of an end of the stem to a plastic state and then shapingthe glass so heated in a press to define a stem press 16 shown insubsequent figures. It will be noted that the free ends of the hairpin 4in FIGURE 1 extend a short distance inside the stem. When the adjacentarea of the stem It) is heated and the stem press is formed, these freeends of the hairpin will be sealed therein and thus define, as will bedescribed below, two spaced ends of two separate filament support wires.The stem press is preferably of the three-cornered type as shownparticularly in FIGURE 15 so that the work components sealed thereinwill extend therefrom in the relative positions thereof shown in FIGURE15, i.e., the short lead-in wire 6 emerges from one corner of the press,the short lead-in wire 3 emerges from a second corner of the press, thelong lead-in Wire 2 emerges from the third corner of the press and thelegs of the hairpin emerge more centrally from the press and spaced fromone another.

At a station subsequent to the stations at which the stem has beenthusly formed, the long lead-in wire 2 and the hairpin s are deflectedoutwardly as shown in FIGURE 2 to provide room for the insertion ofworking tools to shape the short lead-in wires 6 and 8. As shown inFIGURE 3 each of the short lead-in wires 6 and 8 have been bent at twopoints to thereby define segments 6a, db and 6c in lead-in wire 6 andsegments 8a, 8b and Se in lead-in wire 8. In the right-hand illustrationin FIGURE 3 the article of work has beenrotated counter-clockwise fromthe position which it occupies in the left-hand illustration of thisfigure and only a fragmentary portion of the long lead-in wire 2 and thehairpin 4 is shown. As shown in FIGURE 4, hooks 6d and dd have beenformed in the lead-in wires 6 and 8. As shown in FIGURE 5, the segment6c of lead-in wire 6 and segment Sc of lead-in wire 8 are bentsubstantially 90 to define segments 6e and 82 respectively extendingsubstantially normal to the longitudinal axis of the stem and pointedtoward one another in substantially the same horizontal plane. Thiscompletes the fabricating operations on the short lead-in wires, each ofwhich is now disposed in a position to receive an end of a filament.

Fabricating operations are now performed on the long lead-in wire 2. Asshown in the right-hand illustration in FIGURE 6, the long lead-in wire2 is bent substantially as shown to define segments 2:; and 2b. As shownin the left-hand illustration in FIGURE 6, the segment 2b is bent 90counterclockwise and then bent substantially further counterclockwiseabout a radius to a substantially paper clip type of configurationidentified by the reference character 20. The paper clip 20 is thenjoined, as by welding for example, to the segment 21) at 2d. The bightof the paper clip 20 is then severed and the two free ends formedthereby are flattened as shown in FIGURE 7. Thus the long lead-in Wirehas been provided from itself with an extra short wire 18 attachedthereto and substantially parallel to the segment 2e thereof. As shownin FIGURE 8, the segment 2e of the long lead-in wire 2 is then rotatedclockwise about 180 so that it is extending substantially parallel tobut pointing in a substantially opposite direction from the direction inwhich the extra short wire 18 extends and hooks are 3,1 stress formed onthe ends of segment 2e and the extra short wire 18. The segment 2e ofthe long lead-in wire 2 and the extra short wire 18 are then shaped asshown in FIG- URES 9 and 11 to thereby bring the hooks 2 and 18brespectively into substantially vertical alignment with the hooks 6d and8d respectively formed on the free ends of the two short lead-in wires 6and 8. Thus a pair of vertical aligned hooks have been provided onopposite sides of the longitudinal axis of the stem 16 for receiving apair of filaments. Lamp filaments 20 and 22 are then presented to thesehooks and the hooks are closed about the ends thereof as shown in FIGURE10.

Although we prefer to obtain the extra short wire 18 from the longlead-in wire 2 by the formation of paper clip 2c, it will be readilyappreciated by those skilled in the art that other means may be employedto provide the common lead-in wire, i.e., long lead-in wire 2 with apair of hooks for receiving one end of a pair of filaments. For example,other forms of closed loops may be employed rather than the paper clipconfiguration. Alternatively, the long lead-in wire may be provided witha hook portion intermediate its ends as well as a hook portion at thefree end thereof, in which case one end of the two filaments would besecured to one of these two hook portions of the common lead-in wire.

The hairpin 4 of the filament support wire is shaped as shown in FIGURE12 and the bight thereof is severed to define two separate filamentsupport wires 40 and 4b. As shown in FIGURE 13 the free ends of thesetwo filament support wires 4a and 4b are bent inwardly substantially 90and outside the filaments. The free ends of these filament support wires4a and 4b are then looped around their respective filaments as shown inFIGURE 14. This completes the fabrication of the 3-lite lamp mountstructure, an enlarged view of which is shown in FIGURE and identifiedgenerally by reference number 24.

In certain of FIGURES 2 to 14, some of the work components not directlyinvolved in the operations illustrated in these particular figures havebeen omitted for clarity of illustration of the particular workcomponents on which operations are being performed. Similarly, certainreference numbers have been omitted in some of the figures for the samereason.

Further lamp manufacturing operations, utilizing the mount 24 of FIGURE15 as one of the work components, are performed in a manner well knownto those skilled in the art, the mount being hermetically sealed to alamp envelope 26 and a base 28 afiixed thereto to provide a finishedlamp as shown in FIGURE 16.

What we claim is:

l. A lamp comprising: an hermetically sealed envelope having alongitudinal axis; a stem disposed in said enelope at an end thereof,the longitudinal axis of said stem being substantially coincident withthe longitudinal axis of said envelope, and said stern having a pressformed on the inner end thereof; a pair of short lead-in wires ofsubstantially the same length secured in said stem press and extendinggenerally longitudinally within said envelope and further extendinglaterally toward one another and substantially normal to thelongitudinal axis of said envelope and terminating short of said axisand having hooks formed in the ends thereof; a long lead-in wire securedin said stern press and extending generally longitudinally within saidenvelope and substantially further than said pair of short lead-inwires, said long lead-in wire further extending laterally and having ahook formed at the end of said laterally extending portion, said hookbeing substantially in register with one of said hooks formed on theends of said short lead-in wires; an extra short wire secured adjacentone end thereof to said long lead-in wire at a point below the point atwhich said long lead-in wire extends laterally, said extra short wireextending laterally and having a hook formed on the other end thereof,said hook being substantially in register with 6 the other of the saidhooks formed on the ends of said short lead-in wires; and a filamentdisposed substantially vertically, extending between and supported byeach of said two pairs of registered hooks.

2. A lamp comprising: an hermetically sealed envelope having alongitudinal aids; a stem disposed in said envelope at an end thereof,the longitudinal axis of said stem being substantially coincident withthe longitudinal axis of said envelope and said stem having athree-cornered press formed on the inner end thereof; a pair of shortlead-in wires of substantially the same length secured in and emergingrespectively from a corner of said threecornered press and extendinggenerally longitudinally within said envelope and further extendinglaterally toward one another and substantially normal to thelongitudinal axis of said envelope and terminating short of said axisand having hooks formed in the ends thereof; a long lead-in wire securedin said stern press, emerging from the third corner of saidthree-cornered press and extending generally longitudinally within saidenvelope and substantially further than said pair of short lead-inwires, said long lead-in wire further extending laterally and having ahook formed at the end of said laterally extending portion, said hookbeing substantially in register with one of said hooks formed on theends of said short lead-in wires; an extra short wire secured at one endto said long lead-in wire, said extra short wire extending laterally andhaving a hook formed on the other end thereof, said hook beingsubstantially in register with the other of the said hooks formed on theends of said short lead-in wires; and a filament disposed substantiallyvertically, extending between and supported by each of said two pairs ofregistered hooks.

3. A lamp comprising: an hermeticaly sealed envelope having alongitudinal axis; a stem disposed in said envelope at an end thereof,the longitudinal axis of said stem being substantially coincident withthe longitudinal axis of said envelope, and said stem having athree-cornered press formed on the inner end thereof; a pair of shortlead-in Wires of substantially the same length secured in and emergingrespectively from a corner of said threecornered press and extendinggenerally longitudinally within said envelope and further extendinglaterally toward one another and substantially normal to thelongitudinal axis of said envelope and terminating short of said axisand having hooks formed in the ends thereof; a long lead-in wire securedin said stem press, emerging from the third corner of saidthree-cornered press and extending generally longitudinally within saidenvelope and substantially further than said pair of short lead-inwires, said long-lead-in wire further extending laterally and having apair of spaced hooks formed therefrom, each of said hooks being inregister with one of said hooks formed on the ends of said pair of shortlead-in wires; and a filament disposed substantially vertically,extending between and supported by each of said two pairs of registeredbooks.

4. A lamp comprising: an hermetically sealed envelope having alongitudinal axis; a stem disposed in said envelope at an end thereof,the longitudinal axis of said stem being substantially coincident withthe longitudinal axis of said envelope, and said stem having a pressformed on the inner end thereof; a pair of short lead-in wires ofsubstantially the same length secured in said stem press and extendinggenerally longitudinally within said envelope and further extendinglaterally toward one another and substantially normal to thelongitudinal axis of said envelope and terminating short of said axisand having hooks formed in the ends thereof; a long lead-in wire securedin said stem press, emerging therefrom at a point substantiallyequidistant from the points of emergence of said short lead-in wires,and extending generally longitudinally within said envelope andsubstantially further than said pair of short lead-in wires, said longlead-in wire 4' further extending laterally and having a hook formed atthe end of said laterally extending portion, said hook beingsubstantially in register with one of said hooks formed on the ends ofsaid short lead-in wires; an extra short wire secured at one end to saidlong lead-in wire at a point below the point at which said long lead-in'wire extends laterally, said extra short wire extending laterally andhaving a hook formed on the other end thereof, said hook beingsubstantially in register with the other of the said hooks formed on theends of said short lead-in wires;

a filament disposed substantially vertically, extending between andsupported by each of said two pairs of regis- G5 a the ends thereof,each of said laterally extending portions terminating in a loop aboutone of said filaments.

References Cited in the file of this patent UNITED STATES PATENTS2,007,933 Braselton July 9, 1935 2,022,219 Ruben Nov. 26, 1935 2,227,324Severin Dec. 31, 1940 2,519,445 Drieschman Aug. 22, 1950 2,733,377 BohmeJan. 31, 1956 2,845,691 Atherton et al. Aug. 5, 1958 2,877,375 PearsonMar. 10, 1959 2,910,611 Jordan et al. Oct. 27, 1959 2,973,451 PlishkerFeb. 28, 1961 2,997,616 Edwards Aug. 22, 1961

1. A LAMP COMPRISING: AN HERMETICALLY SEALED ENVELOPE HAVING ALONGITUDINAL AXIS; A STEM DISPOSED IN SAID ENVELOPE AT AN END THEREOF,THE LONGITUDINAL AXIS OF SAID STEM BEING SUBSTANTIALLY COINCIDENT WITHTHE LONGITUDINAL AXIS OF SAID ENVELOPE, AND SAID STEM HAVING A PRESSFORMED ON THE INNER END THEREOF; A PAIR OF SHORT LEAD-IN WIRES OFSUBSTANTIALLY THE SAME LENGTH SECURED IN SAID STEM PRESS AND EXTENDINGGENERALLY LONGITUDINALLY WITHIN SAID ENVELOPE AND FURTHER EXTENDINGLATERALLY TOWARD ONE ANOTHER AND SUBSTANTIALLY NORMAL TO THELONGITUDINAL AXIS OF SAID ENVELOPE AND TERMINATING SHORT OF SAID AXISAND HAVING HOOKS FORMED IN THE ENDS THEREOF; A LONG LEAD-IN WIRE SECUREDIN SAID STEM PRESS AND EXTENDING GENERALLY LONGITUDINALLY WITHIN SAIDENVELOPE AND SUBSTANTIALLY FURTHER THAN SAID PAIR OF SHORT LEAD-INWIRES, SAID LONG LEAD-IN WIRE FURTHER EXTENDING LATERALLY AND HAVING AHOOK FORMED AT THE END OF SAID LATERALLY EXTENDING PORTION, SAID HOOKBEING SUBSTANTIALLY IN REGISTER WITH ONE OF SAID HOOKS FORMED ON THEENDS OF SAID SHORT LEAD-IN WIRES; AN EXTRA SHORT WIRE SECURED ADJACENTONE END THEREOF TO SAID LONG LEAD-IN WIRE AT A POINT BELOW THE POINT ATWHICH SAID LONG LEAD-IN WIRE EXTENDS LATERALLY, SAID EXTRA SHORT WIREEXTENDING LATERALLY AND HAVING A HOOK FORMED ON THE OTHER END THEREOF,SAID HOOK BEING SUBSTANTIALLY IN REGISTER WITH THE OTHER OF THE SAIDHOOKS FORMED ON THE ENDS OF SAID SHORT LEAD-IN WIRES; AND A FILAMENTDISPOSED SUBSTANTIALLY VERTICALLY, EXTENDING BETWEEN AND SUPPORTED BYEACH OF SAID TWO PAIRS OF REGISTERED HOOKS.